Bathtub



FIG. 1 is a perspective view of the first embodiment of a bathtub incorporating my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a front view thereof, the rear view thereof being identical to the front view; and,

FIG. 5 is a lateral view thereof, the opposite lateral views being identical to one another.

Those portions of the article not shown form no part of the claimed design. 

CLAIM The ornamental design for a bathtub, as shown and described. 